Motor-driven mechanical hammer



March 2l, 1933. M. G. H. OUSBCK L MOTOR DRIVEN MECHANICAL HAMMER Filed Jan. ll, 1952 2 Sheets-Sheet l Q Tra/@MEMS March 21, 1933.

M. G. H. OUSBCK MOTOR -DRIVEN MECHANICAL HAMMER Filed Jan. 1v1, 1932 2 Sheets-Sheet 2 ATTBNEYS Patented Mar. 211, 1933 UNITED STATES PATENT OFFICE- MATS GSTA :maarl oUSBcK, or STOCKHOLM, swnnniv, AsSIGNoR 'ro RAGNAR Barnes vor STOCKHOLM, SWEDEN Y Moron-nerven MEcHANrcAL HAMMER.

Application led January 11, 1932, Serial No. 585,857, and in "Sweden January 12,1931.

A further object is to provide a hammerL Yconnected with a tool-holder, i and vhaving means for changing the position of said toolholder in conformity with the length of the Stroke of the reciprocating member. Y

Still another object is to provide a hammer having a connecting rod or link mechanism combined With a .disk-shaped cross-head rotated by a driving shaft, ysaid disk being iitted obliquely in relation to said shaft, and transmitting to the striking member a movement in the approximate direction of the `25 rotating shaft. Y

The invention will be more clearly `understood from the following detailed description, when studied in connection with the accompanying .drawings showingpa preferred embodiment of thekinventive idea.

In .the drawings: Y

Figure 1 shows a motor-driven hammer in side elevation and, partly, in vertical section.

Figure 2 is the side view of a regulating collar. n Figure 3 is a top-view of a tool-holder.

Figure 4 shows another modication of the hammer. n

VThe hammer Vshown in Figs. 1-3 comprises a tool-holder 2 adjustably connected With a vcasing 1, by .means of a sleeve 3. An electric motor 4 is situated Within the upper part of the casing l, which is provided with a handle 5. The driving shaft 6 of the motor 4 is connected, by any suitablemeans, With a cross-head 7 having the shape of a disk, and

rotating on ball-,bearings in a guide ring 8 provided withl a'r'ound VSide surface. The

ried by .diametrically opposed studpinsj16,

.one of Which is shown by the dotted lines in Y the drawings. These studpins 16 enable the n disk 7 to turn Within the casingy l. Due vto this arrangement, the studpins 16 Will absorball .55 the shocks occurring during the operation vof the hammer, so that these shocks will `not be transmitted to the driving shaft 6.

The disk 7 is rigidly connectedyvith a crank web '9, and a connecting rod Vor link'60 10 is pivoted tolsaid crankvWeb. The rod 10 is joined toa guide piston 11 by means of a ball joint. A spring 12 is Situatedbetween the guide pisto'nlI anda strikingv Weight 13,`and transmits the movement ot the/piston' 11 to theweightl. i 'V i A Vguide sleeveflt is situated Withinthe lsleeve 3,`andv is used as a guideffor the piston 11, the Weight 18 andthe tool-holder 2. A regulating collar 15 shown in side eleva-70 tion in Fig.,2, surrounds the lower part of the vcasing 1 and the. upper portion V of ,the sleeve. The collar 15 may be rotated Within limits prescribed by a Slot 17 a and a guide stud 17 projecting through said slot, and-:75V

irmly connected to ,the casing 1. ,Another oblique slot 18 is situated on the opposite side of the collar 15, andis used to guide f a stop pin 19 passing through al corresponding opening inthe casing 1, and tted in that. end ofthe ring 8, which slants away from vthe motor shaft 6. It is'thus possiblev to change the anglehformed bythe ring 8 andthe shaft -6 by turning the collar 115` thevariation of this angle resulting in a change of the length of stroke of the piston'll, reciprocated bythe rod 10 and the crank Web 9. The ring 8 may be locked incertain positions by inserting the stop pin 19 into one of the notches 20 provided in the casing V1. A third slot v21 is90 formed approximatelyparallel tothe Slotl8, and is situated b'elovir Said Slot on the collar 15. A pin 22 firmly connected `to the sleeve 3 projects through the slotJ 21, so that the ksleeve 3 and the tool-holder 2, connected there- 95 with, can` be moved When the collar vis vrotated, anda certain position of' the l'toolholder 2 Will'correspond .to a `certain length ofthe stroke. 0 ring 8 situated Within the casingl is cary A'guide pin is rigidlyfconnected to the" '100 ingly shifted, while the pin 22moves in the casing 1 and projects through an opening formed in the sleeve 3. The pin 25 is situated on the other side of the collar, approximately in line with the slot 21.

The hammer operates as follows:

As soon as the electrical motor 4 has beenl started, the rotation of the motor shaft 6 will be transmitted to the disk 7, the crank web 9 and the rod 10. The rod 10 will reciprocate theV piston 11, which will transmit its movement to the striking weight13 through the intermediary of the spring 12. The rotation of the disk 7 will, therefore, be transformed into a reciprocating movement of the striking weight 13, this transformation taking place without any strain, and with a very small loss of power. The weight'13 will move approximately in line with the rotating shaft.

Toadjustthe length of the stroke, it is necessary to change the position of the ring 8 with vrespect to the shaft 6. This is done by releasing the stop pin 19 from -its notch andturning the collar 15. The pin 19 will then movewith respect to the slot 18. The tool-holder 2 is at the same time correspondoblique slot 21. After the adjustment of the "stroke has been completed, the stop pin 19 is inserted intoone of the notches 20 corresponding to the new adjustment.

Fig. 4 shows another modification of the motor-driven hammer, comprising a casing 1, a tool-holder 2, a sleeve 3 and electric'driving -means 4 arranged substantially in the same manneras in the modification shown in Figs. l-3. The driving shaft 6 is connected by means ofa joint 26, with a disk-shaped crosshead 7 adapted to rotate on ball bearings 27 carried by a guide ring 8. Said guide ring 8 is` connected with a lspring 28 carrying a small plate 29, which presses against -an edge ,ofthe casingfl. One end of the rod 10 is connected'with the Vcross-head 7 by means of aplate 30 screwed to said cross-head, while the other end is connected with afguide piston 11 by means ofL a ball joint.' The lower end Vof the piston 11 ts into an opening within the'weight 13, which is connected with said piston by means of a spring 12. Another spring 31 is situated within the tool-holder 2 and serves to diminish the repercussions of i the hammer.

A second sleeve'32 is situated within the upper part of the sleeve 3. The

position of the ring 8 may be adjusted by means of a stop pin 19 in a way similar to that described in connection with the modification shown in Figs. 1-3.

. It is, of course, possible to give the tool described while keeping within the scope -lcovered by the invention. The link 10 may thus beunited tothe piston 11 by a'vpin joint "instead of the suggested'ball joint, in which case thel pistonrmustrrotate in the lining sleeve. `A non-rotating washer or the like is collar. A i

3. A motor-driven hammer, comprising a" then suitably inserted between the piston and the spring 12.

The stop pin 19 may be replaced by an ordinary pin, thus eliminating the necessity of making notches in the shell. If an adjustment collar is used, and'placedA at a point where the operator usually holds the tool with oneV hand while drilling, the regulation of the strokecan be undertaken most conveniently andwithout req'u'iringa fresh'hold.'

The power may be supplied from some other source thanA an electric motor in the handle of the tool, for example from a stationary motor or the like, .by means of a flexible cable. c A j The ratio of angularity between the two slanting grooves in the collar 15 maynaturally vary according to the desired change of Vposition between the tool-holder and the striking 'weight' in relation to the changed Obliquity of the disk. 1

The adjustment of the disk 7, inorder to regulate thev stroke, can also be carried out by'SOme-Other means than the one shown by the drawings, both in case of small and big hammers. F or large hammers, such'as forging hammers, the regulating mechanism may suitably be made in some manner, which enables itvto be operated by a pedal. In handhammers the strokeY adjustment may be coinbined with a spring or the likefor placing the disk in either end position.`

1.'.A motor-driven hammer, comprising a driving shaft, means for rotating said shaft, a cross-head connected with and rotated by said shaft in an oblique plane with respect to saidshaft, a reciprocating striking member, means including a link member for connecting said striking member and said cross-head,

Vand meansl for simultaneously adjusting the Vwithin said casing rotated by said driving shaft, a reciprocating striking member,

means including a link member for connect-L ing said striking member and said cross-head, a regulating collar surrounding said casing, a member connected with said collar for adjusting the position of said cross-headwith surrounding a part of said casing and connected with said'tool-holder,-and means for connecting said sleeve and said regulating driving shaft, means connected with 'said shaft for rotating the same, a reciprocating striking member, a crosshead connected with and rotatedby said shaft in an oblique planeI with respect to the central line along which respect to said shaft, a tool-holder, Sleeve? said striking member reciprocates, said central line meeting said crosshead substantially at the center thereof, means including a link member for connecting said striking member and said crosshead substantially on said line,

and means connected with said crosshead for adjusting the position thereof With respect to said line.

4. A motor-driven hammer, comprising a casing, a motor having a driving shaft proj ec-ting into said casing, a guide ring Within said casing, bearings connected with said guide ring, a crosshead rotated on said bearings by said driving shaft, a striking mem- Y ber reciprocating along its central line which meets said crosshead substantially at the center thereof, means including a link member for connecting said striking member and said crosshead substantially on said-central line, a regulating collar surrounding said casing, and a member connected with said collar for adjusting the position of said crosshead with respect to said shaft. Y

5. A motor-driven hammer, comprising a casing, a motor having a driving shaft and connected With said casing, a guide ring within said casing, bearings connected with said guide ring, a crosshead rotated by said driving shaft, a reciprocating striking member, means including a link member for connecting said striking member and said crosshead, a regulating collar surrounding said casing, a slot formed in said collar, a plurality of openings formed in said casing, and a pin projecting through said slot and one of said openings and adapted to adjust the position of said crosshead with respect to said shaft.

In testimony whereof I have aflixed my signature.

MATS GosTA HARRY oUsBcK. 

